Monday, June 17, 2013

Arixtra Molecule

Arixtra Molecule

As I mentioned last week, Arixtra is a synthetic anticoagulant drug that's related to natural compounds found in humans. It's also known by its generic name, "fondaparinux," though we always called it Arixtra in my doctoral research lab. It's a carbohydrate with a total of five rings, and it's related to the natural carbohydrates heparin and heparan sulfate, which are also used as anticoagulants (though those molecules are much bigger!)

From a structural point of view, an interesting aspect about Arixtra is that it has so many sulfates (the clusters of yellow and red atoms in the model above). Sulfates are more common in these kinds of carbohydrates compared to peptides such as my Endorphin Molecule necklace. From the beader's point of view, this changes the color balance of the piece, because so much more of the mass of the molecule is taken up by sulfates as opposed to nitrogen atoms. However, since my fellow-chemist friend that commissioned this piece specifically requested CPK colors, the big color decisions were out of my hands.

Chemical Flexibility

Like the Endorphin necklace, this piece is quite flexible, just like a real molecule.

Real molecules do, however, tend to prefer particular "poses" over others, which can change depending on their situation. We're not exactly sure which configuration Arixtra prefers in its molecular state, though it might look like a big glob of atoms like this:

Arixtra as Jewelry

Since this piece is an object d'art, it's not going to be incorporated into jewelry. However, it's about 7 inches long, which is just about the right length for a bracelet.

But since this piece is so asymmetrically dimensional, and full of branches of beads that might get caught on a stray thread from a sweater, I'd be much more comfortable wearing it as a necklace. I pinned it to one of my jewelry busts to see what it would look like as a necklace.